Covering a bald spot with Henna?

I have this bald spot in the back of my head. It's not shiny and smooth but VERY thin. My hair color is very similar to Henna ink. I was thinking of covering it with Henna ink so it kind of blends in with the rest of my hair and is less noticeable. Has anyone tried this before? Any possible side effects that could happen?

The scalp is naturally oily and does not take henna well without first removing those oils thoroughly. The stain then fades after about a week, so you would have to reapply often. Also, there would be no way to just henna the scalp without getting any henna on your hair, which would change the hair color. If you are still interested in trying henna to cover the bald spot, I suggest heading over to the "Henna for Hair" site, so that you can check out the colors, etc... that henna can change your hair to. Henna is very good for the hair and scalp. Any possible side affects are likely to be caused by allergies to either citrus or essential oils in the paste, actual henna allergies are very rare.